<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1.0">	
	<meta http-equiv="X-UA-Compatible" content="IE=edge">
	<title>登录页面</title>
      <!-- 新 Bootstrap 核心 CSS 文件 -->
     <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
 
     <!-- 可选的Bootstrap主题文件（一般不使用） -->
     <script src="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap-theme.min.css"></script>
 
     <!-- jQuery文件。务必在bootstrap.min.js 之前引入 -->
     <script src="https://cdn.bootcss.com/jquery/2.1.1/jquery.min.js"></script>
 
     <!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
      <script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
     <style>
	      body{
		   margin-left:auto;
		   margin-right:auto;
		   margin-top:100px;
		   width:40em;
		   border-bottom-style：block；
		  }
		  #checkcodeimage{
		  width:400px;
		  height:75px;
		  }
	  </style>
</head>
<body>

  <form class="form-horizontal" role="form">
	<div class="form-group">
		<label for="username" class="col-sm-2 control-label">用户:</label>
		<div class="col-sm-10">
			<input type="text" class="form-control" id="username" 
				   placeholder="请输入用户名">
		</div>
	</div>
	<div class="form-group">
		<label for="password" class="col-sm-2 control-label">密码:</label>
		<div class="col-sm-10">
			<input type="password" class="form-control" id="password" 
				   placeholder="密码">
		</div>
	</div>
	<div class="form-group">
	  <label for="checkcode" class="col-sm-2 control-label">验证码:</label>
	  <div class="col-sm-10">
	      <input name="code" class="form-control" id="checkcode" placeholder="验证码">
	  </div>
	  <div class="col-sm-offset-2">
      <img src="images/smlie.jpg" onclick="self.location.reload();" id="checkcodeimage"/>
	  </div>
	</div>
	<div class="form-group">
		<div class="col-sm-offset-2 col-sm-10">
			<div class="checkbox">
				<label>
					<input type="checkbox">请记住我
				</label>
			</div>
		</div>
	</div>
	<div class="form-group">
		<div class="col-sm-offset-2 col-sm-10">
			<div class="col-sm-2"><button type="submit" class="btn btn-default"><a href="main.html">登录</a></button></div>
			<div class="col-sm-offset-3"><button type="resert" class="btn btn-default">重置</button></div>
		</div>
	</div>
  </form>

</body>
</html>